According to The New York Times, top U.S. executives at Wal-Mart (NYSE:WMT) were tipped off in 2005 by a former Wal-Mart employee in Mexico, who detailed the dates, amounts and recipients of bribes paid to speed the construction of stores across Mexico. U.S. executives investigated and confirmed the claims. At that point, Wal-Mart’s top management shut down the investigation. The company did not reveal the bribery to either U.S. or Mexican officials until last year, when it discovered that the Times had obtained documents relating to the matter.

Here are five things to know about the Wal-Mart bribery case:

Amount of bribes paid to Mexican officials: At least $24 million, according to Wal-Mart’s internal investigation, which found the bribery “widespread” across every region of Mexico.

Who knew about the bribes: Wal-Mart’s internal investigation revealed that top Mexican executives, including CEO Eduardo Castro-Wright, knew of the bribes and took measures to conceal them from U.S. management. Top U.S. executives knew of the problem by late 2005.

Why Wal-Mart stopped the investigation: Wal-Mart feared that revelation of the bribery would compromise its growth and provide ammunition to opponents in the U.S. Fully 20% of Wal-Mart’s stores are located in Mexico.

How the company responded: U.S. executives upbraided its investigators for being too aggressive, transferred their evidence to Mexico and placed Wal-Mart’s Mexican general counsel in charge of the investigation — despite claims that he had approved the bribes. The Mexican general counsel dismissed the allegations. U.S. management accepted his verdict.

What could happen: Under the Foreign Corrupt Practices Act, U.S. companies can be held liable for illegal actions like bribery even outside the U.S. Wal-Mart could face hefty U.S. fines, an expensive multi-year federal probe and additional regulatory scrutiny, Reuters noted.